(452d) Plasmon Enhanced Synthesis of Single Atom Platinum Catalyst

Plasmonic photocatalyst can generate photoexcited electrons by absorbing the visible light that powers energy extensive catalytic reactions such as CO2 reduction, water splitting and solar energy conversion with high efficiency. We have successfully synthesized single atom plasmonic catalyst (SAC) by visible light induced deposition of Platinum (Pt) single atoms on refractory plasmonic titanium nitride (TiN) nanoparticles. Titanium nitride nanoparticles can absorb broad spectrum solar light to generate photoexcited electrons which reduce Pt precursor salt to deposit as metal atoms on the surface. We are studying the effect of photo deposition process conditions such as wavelength of light, light intensities, and duration of irradiation on the deposition pattern of the Pt single atom, the SAC formation has been confirmed through TEM imaging and XPS results. We study the distinction and significance between two processes: whether the Pt precursor undergoes reduction into Pt metal in the solution before attaching to the TiN surface, or if it adsorbs onto the TiN surface before undergoing reduction into Pt metal. DFT calculations were reported to investigate interactions between Pt and TiN such as Pt active site determination, aggregation energy, and charge analyses. These calculations aid in refining catalyst synthesis by allowing us to understand the underlying processes that are occurring at a molecular level. The findings of this study can be used to develop a visible light mediated synthesis method for single atom plasmonic catalysts under mild conditions, which has been a bottleneck for their widespread applications.